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IV. EXHIBIT D - MINING PLAN <br />4.01 General <br />Mining and reclamation will proceed in four phases beginning from the northwest and moving <br />in a clockwise manner to the southeast. The process area will be located in the western area of <br />the mining limits and encompass approximately 4 acres. The mining phases will be employed <br />to: 1) develop the quarry in a manner that will disturb only limited areas at a time; 2) facilitate <br />reclamation of mined slopes in inactive areas in a timely manner; and 3) accommodate <br />operational considerations. The configurations shown for all phases are the most aggressive <br />configurations which are likely to be practical from a geotechnical perspective. Less aggressive <br />configurations are possible. Operational considerations, rock quality, slope stability, and visual <br />impacts will all influence the actual final build-out for any phase, which may be less extensive <br />than the geometries shown. <br />The excavation has been divided into four phases, as shown on the maps in Figure D. Each <br />figure represents a "snapshot" in time. The actual operation will be more continuous with <br />reclamation being performed concurrent with the mining operation. Benches and highwalls <br />above elevation 5800 ft will be developed by leaving intentional short breaks 50 ft to 75 ft wide <br />in the highwalls, and leaving diagonal haul roads in place in an attempt to break up the <br />horizontal lines created during standard highwall and bench mining (see Figure D-2). These <br />benches will be reclaimed by backfilling. <br />Front Range Aggregates has indicated that they intend to use the quarry for water storage after <br />mining is complete. The approximate water surface elevation will be 5790 ft. Benches and <br />highwalls below elevation 5800 ft will not need to be backfilled as they will be underwater once <br />mining is complete and the pit is used as a water storage reservoir. <br />Prior to mining, a processing plant platform will be constructed by placing fill in the area shown <br />on Figure D-1 from elevation 5790 ft to elevation 5820 ft. Side slopes will generally be at an <br />inclination of approximately 3:1 (horizontal:vertical). This will provide a processing area that is <br />above the floodplain. <br />Three ephemeral drainages exist within the mining limits and have been designated 1, 2, and 3 <br />from west to east. The drainages have been used as natural limits to each mining phase. Each <br />drainage will not be disturbed until the next mining phase is implemented. <br />4.02 Phase IA and IB <br />Phase I will consist of two sub-phases, IA and IB, which will develop the northwest corner of <br />the quarry east to drainage 2. Phase IA is an "experimental" initial excavation which will be <br />done well within the mining limits in order to observe actual performance of the benches and <br />highwalls in various orientations. Once this has been done, Phase IB will be implemented for <br />production by beginning mining at the outer edge of the mining limits in the northwest corner. <br />Benches and highwalls will be developed from the northwest corner east to drainage 2 and <br />south towards the process area, beginning at the northern and western mining limits and <br />working down from there. Some of the final benches and highwalls above elevation 5800 ft in <br />will begin to be reclaimed by backfilling the benches to reduce visual impacts. Phase IB will be <br />mined to platform elevation 5800 ft resulting in the bench and highwall configuration shown in <br />figure D-1, Mining Plan. <br />\\Server0l\common\PROJECTS\106052-000 Parkdale Mine Plan\R. Records and Correspondence\R.11 Reports\Pennit_1_24_08.doc